[gumba]

I posted this a few places with no response. It seems like I need a tach adapter, but which one?

I tried to swap in a '75 tach into the '79 turbo. The turbo has the stock cdi. The tach doesn't read. I tried another '75 tach, same thing. I checked both tachs on my '86 3.2 w/Electromotive hpv 1 and they both work fine. It's not a wiring issue, as I checked that multiple times with both tachs.